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51.
本文分析了洞庭湖流域生态环境破坏对洪涝造成的影响,指出流域生态环境受到破坏主要是人类违背自然规律、破坏森林植被、盲目围湖造田、生产及建设性破坏河道及湖滩所致。文章还就根治洞庭水患的关键性措施——搞好生态恢复,提出了几点意见。  相似文献   
52.
对我国水资源可持续利用的一点思考   总被引:3,自引:0,他引:3  
姚红  单霞  左玉辉 《四川环境》2004,23(5):76-78
按照“认识——规划——建设”的思路,分析了我国水资源开发利用中所面临的主要问题和挑战,提出水资源可持续开发利用的策略和对策,特别提出分质供水和中水回用相结合的供水方式,作出了各地区重点建设项目的构想。  相似文献   
53.
利用煤矸石制备低环境负荷型水泥的研究   总被引:3,自引:0,他引:3  
煤矸石是我国排放量最大的工业废渣之一,破坏生态环境,不利于可持续发展。本文分析与研究了煤矸石的综合利用现状,着重探讨了煤矸石在我国水泥工业中的应用,并从材料学、热学和环境学等交叉学科入手研究了利用煤矸石生产低环境负荷型水泥的控制理论与技术及其社会经济效益。  相似文献   
54.
本文通过对居室环境概念的阐述,剖析了人与居室环境功能的关系,并指出了居室环境对人行为的规范作用及营造良好居室环境的重要性。  相似文献   
55.
The aim of this study is to examine the relationship between environment and personal well-being using a sample of 562 urban employees from three cities in Liaoning province in the People’s Republic of China.In contrast to previous studies,this study controlled positive affectivity (PA),negative affectivity (NA),job satisfaction and Big Five personality traits.In addition,the research variables of personal well-being index (PWI),positive affectivity,negative affectivity,job satisfaction,Big Five,and environmental satisfaction are measured with multi-item scales.The research finds that environmental satisfaction is positively related to personal well-being,suggesting that improvement of the natural surroundings in the cities can improve people’s well-being.  相似文献   
56.
定位研究了25a来缙云山银木荷林物种组成及多样性在自然演替过程中的动态变化。结果表明,银木荷林维管植物物种由57种(隶属于24科,46属)减少到38种(隶属于19科,26属)。林下草本和层间植物逐渐消失,胸径大于7.5cm的乔木层树总胸断面积有所减少。尽管群落物种组成以及多样性发生改变,但是银木荷依然是优势树种,处于林冠层,而林冠亚层的白毛新木姜子、四川山矾、长蕊杜鹃逐渐增多,短刺米槠逐渐减少。群落乔木层4个α多样性指数都呈下降趋势,丰富度指数由2.98下降为1.99,Shannon-Wiener指数25a间减小了0.34,Simpson指数和Pielou指数变化都很小;β多样性分析结果显示,银木荷群落的物种差异很大。研究表明,25a间群落物种差异显著。揭示缙云山银木荷林自然演替过程中的物种组成和多样性变化规律,可为缙云山保护区及长江流域中上游亚热带常绿阔叶林的银木荷群落的管理提供一定的参考价值。  相似文献   
57.
The aim of the research was to evaluate, at site scale, the influence of freezing and freeze/thaw cycles on the survival of faecal coliforms and faecal enterococci in soil, in a climate change perspective. Before the winter period and during grazing, viable cells of faecal coliforms and faecal enterococci were detected only in the first 10 cm below ground, while,after the winter period and before the new seasonal grazing, a lower number of viable cells of both faecal indicators was detected only in some of the investigated soil profiles, and within the first 5 cm. Taking into consideration the results of specific investigations, we hypothesise that the non-uniform spatial distribution of grass roots within the studied soil can play an important role in influencing this phenomenon, while several abiotic factors do not play any significant role. Taking into account the local trend in the increase of air temperature, a different distribution of microbial pollution over time is expected in spring waters, in future climate scenarios. The progressive increase in air temperature will cause a progressive decrease in freeze/thaw cycles at higher altitudes, minimising cold shocks on microbial cells, and causing spring water pollution also during winter.  相似文献   
58.
International cooperation to address climate change now stands at a crossroads.With a new international regime for emissions reduction established by the Durban Platform, "New Climate Economics(NCE)" has become a research hotspot.The need for urgent action to combat climate change has prompted discussion on reforms of economic growth patterns and the energy system.The industrial civilization,therefore,now faces a transition towards a new pathway for ecological sustainability.NCE explores new economic concepts,theories,and analytical methods to design a balanced pathway for sustainable growth and emission reduction.Instead of getting trapped in discussions on allocation of emission reduction responsibilities and obligations among countries,NCE pays more attention to developing win-win multilateral cooperation mechanisms that facilitate collaborative RD and knowledge sharing.In addition,NCE studies incentives for low-carbon transition,turning carbon emission reduction into a domestic need for countries to increase their international competitiveness.To achieve the 2°C target,most countries around the world face challenges of insufficient emission allowances to cover expected emissions associated with their projected economic growth.As carbon emissions rights becomes an increasingly scarce resource,increasing the carbon productivity of the economy turns to be the critical path to address the dilemma of green or growth.NCE studies the historical evolution of carbon productivity for countries at different development stages as well as ways to enhance such carbon productivity.This type of study provides invaluable lessons for emerging economies to reach their own emission peaks without losing the momentum of growth.Replacing fossil fuels with new and renewable energy has proven to be an inevitable choice for reshaping the energy system and addressing climate change- it has already become a global trend.NCE studies incentives for new energy technology innovation and deployment provided by carbon pricing,and sheds light on the co-benefits of climate change mitigation,such as resource conservation,environmental protection,and energy security.The role of carbon pricing in promoting intemational RD cooperation and technical transfer will also be studied.The shift in consumption patterns is another key factor enabling a low-carbon transformation.Therefore,NCE also explores the theoretical work on new values of wealth,welfare and consumption,new lifestyles in the context of ecological civilization,concepts and implementation of low-carbon urban planning in developing countries,and the impacts of consumption pattern changes on social development,material production,and urban infrastructure construction.  相似文献   
59.
Based on the analysis on the global economic crisis,climate change crisis and their mutual underlying reasons,the authors believe that low-carbon economy has become an inevitable choice to break through the dual crises,coordinate the economic development,and protect the global climate.The global trend of low-carbon economy finds expression in Green Recovery currently,while,in a long run,it will give rise to a new pattern of world competition in politics,economy,technology,trade and finance.The impact of the...  相似文献   
60.
圆锥形零件冲压成形过程分析   总被引:1,自引:0,他引:1  
通过分析圆锥形零件变形毛坯上不同部分在成形中的作用,揭示了该类零件的冲压成形特点,得出了悬空侧壁部分的变形状态是该类零件成形的关键,而径向拉应力是实现侧壁部分成形的必要条件,同时也是这部分冲压成形成败的关键。为此,经力学分析得出了侧壁部分径向拉应力的解析式和造成圆锥形零件破裂的最大径向拉应力的计算式,为进一步研究提供了理论基础。  相似文献   
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